[Lldb-commits] [lldb] [LLDB][NativePDB] Estimate symbol sizes (PR #165727)

[Jonas Devlieghere via lldb-commits]

================
@@ -1130,16 +1130,47 @@ void SymbolFileNativePDB::AddSymbols(Symtab &symtab) {
   if (!section_list)
     return;
 
-  for (auto pid : m_index->publics().getPublicsTable()) {
+  PublicSym32 last_sym;
+  size_t last_sym_idx = 0;
+  lldb::SectionSP section_sp;
+
+  // To estimate the size of a symbol, we use the difference to the next symbol.
+  // If there's no next symbol or the section/segment changed, the symbol will
+  // take the remaining space. The estimate can be too high in case there's
+  // padding between symbols. This similar to the algorithm used by the DIA
+  // SDK.
+  auto finish_last_symbol = [&](const PublicSym32 *next) {
+    if (!section_sp)
+      return;
+    Symbol *last = symtab.SymbolAtIndex(last_sym_idx);
+    if (!last)
+      return;
+
+    if (next && last_sym.Segment == next->Segment) {
+      assert(last_sym.Offset <= next->Offset);
+      last->SetByteSize(next->Offset - last_sym.Offset);
+    } else {
+      // the last symbol was the last in its section
+      assert(section_sp->GetByteSize() >= last_sym.Offset);
+      assert(!next || next->Segment > last_sym.Segment);
+      last->SetByteSize(section_sp->GetByteSize() - last_sym.Offset);
+    }
+  };
+
+  // the address map is sorted by the address of a symbol
----------------
JDevlieghere wrote:

```suggestion
  // The address map is sorted by the address of a symbol.
```

https://github.com/llvm/llvm-project/pull/165727